Spring bicycle-fork.



E. W. HOAG 8: G. R. KITTLE.

SPRING BIGYGLE FORK.

APPLICATION FILED MAY5, 1908.

Patented Oct. 20, 1908.

2 SHEBTS-BHBET 1.

E. W. HOAG & G. R. KITTLE.

SPRING BIOYOLE PORK.

APPLIUATIOH rum) MAY 5, 1908.

2 SHEETS-SHEET 2.

Patented Oct. 20, 1908.

UNITED STATES Parana or ion.

EDWARD W. HOAG AND CHARLES KI'TTLE, OF LOS ANGELES, CALIFORNIA.

SPRING- BICYCLE-FORK.

Specification of Letters Patent. Application on Kay 5, 1908. Serial No. 530,915.

Patented Oct. 20, 1908'.

- To all whom it may concern:

Be it known that we, EDWARD WQHOAG and CHARLES R. KITTLE, citizens of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in Spring Bicycle Forks, of which the following is a specification.

This invention relates to an improved form of spring fork designed to obviate the difficulties heretofore experienced with such fork. These difficulties consisted mainl in the lateral non-rigidity of the front w el so that it was liable to come into contact with the fork, especially in turning curves where the stress upon the wheel is not perfectly vertical.

To overcome these difficulties we have provided a spring fork which will resiliently support the frame from the front wheel and at the same time hold it against undesired lateral motion relative to the frame. Further, we have provided a resilient means of such a nature that the wheel is allowed a long movement relative to the frame, thus earrying the frame smoothly at all times. We accomplish this by means of the device described herein and illustrated in the accompanying drawings, in which:

Figure 1,is aside elevation of a motorcycle provided with our improved fork. Fig. 2,is an enlarged rear elevation of the spring members of the fork. Fig. 3,is a section taken on line 3?3 of Fig. 2. Fig. 4, is a perspective detail of the bracket b means of which the spring members are secured to the fork head.

We have illustrated in the drawings a motor-cycle, spring fork of the character of our invention most usually being ap lied to motor-cycles, but it is obvious that t e fork may be applied as well to a wheeled vehicle of any sort.

In the drawings -5 designates va frame of a motor-cycle of typical construction supported by wheels 6 and 7. The usual. equipment of front fork 8 is shown, our spring fork including in combination a comparatively rigid member which forms a base member for our fork and which is best sup lied by the standard fork. It will be understood that any form of fork may be used, the construction not being limited to forks having a made in any con cone 21 to three piece crown as illustratedirr. the drawings. 4, x v

A bracket 9, shown in detail in Fig. 4, is provided to secure the upper ends of resilient members 10 to the fork crown, bolts 11 be' used for this pur ose. This bracket may be uration to suit the form of the fork to which itis designed to be attached and is not necessarily constructed as shown in the drawings.- The object of this bracket is to pivotally support the upper end of resilient member 10 and this is convenientl done by a bolt 12 passing through the bran e't' and through the upper ends of plungels 13. These plungers are adapted to reciprocate in cylinders 14, heavy col ed springs 15 supporting the plungeis in their normal position as i ustrated. The lower ends of cylinders 14 are each provided with a plug 16 upon which spring 15 rests and a rod 17 pro- I j ecting upwardly from the plu inside of the spring forms a positive stop or the downward movement of the plungers thereby preventing such an excessive movement as may throw the rider from the motor-cycle. The lower ends of plugs 16 are flattened and are bored to receive axle 18 of front wheel 7. A small connecting member 19 is adapted to connect the wheel axle with the lower endsof fork 8 on each side, the ends of the fork being secured by means of bolts 20. As shown 1n 2 these bolts are provided with a shoulder so that they may be tightly screwed up on the end of the fork and connecting pieces 19 will still be allowed to freely rotate around the bolt. The end of connecting piece 19 which connects with the wheel axle-is held between cone 21 and sleeve 22 formed as a part of nut 23. The length of this sleeve is such that iece 19 is tightly pressed ainst lock it in osition on the e and allow the lower on of plug 16 to rotate freely around the sleeve.

From the foregoing construction it will be seen that any u ward movement of front wheel 7 will be a sorbed by springs 15 and that the excessive upward movement will be reventedby means of rod 17. To provide or absorbing the rebound which would otherwise throw the frame of the motor-c 010 u wardly a small cylinder 24 is provide on t '0 rear side of each of c linders 14 and coiled springs 25 therein are a aptedto prevent the upward movement of rods 26. These rods are adjustably secured to studs 27 mounted on plungers 13 so that springs 25 act directly upon the plungers. v Springs 25 are lighter in action than springs 1 5 the ratio in strengthbetween the two springs being determined by the weight of the motor-cycle and other condi tions. Upon the rebound of springs 15 and the consequent tendency to force the frame upwardly, springs 25come into action and resiliently absorb the u ward movement. Thus it will be seen that t e wheel may have considerable vertical movement without any sensible movement of the frame as the movements of the wheel in both directions are entirely taken up and absorbed by the two sets of springs.

Cylinders 14 are secured together at their upper ends by a cross sta 30 brazed or otherwise secured to them. bus, when the axle is secured between the lower ends of the resilient members the whole structure forms a solid and ri id rectan is which must move as a whole an will there ore not allow any irregular or lateral movement of the wheel. ThlS rigidity against lateral movement is also promoted by having connectin pieces 19 of as short extent as possible an providing long bearings for the same on bolts 20, as shown in Fig. 2. Thus the wheel is prevented from binding against the fork by any lateral motion of its axle.

In Fig. 1, the application of our fork to the rear seat of a motor-cycle is illustrated' In this position resilient members 10 are inverted from their position for .the front fork, cylinder 14 bein connected. to seat post 30 at the top and p unger 13 connected to the rear wheel axle below. The customary foot rest 31 is rovided, being artly broken away in the il ustration to disc ose the resilient member behind it. By this means the rear seat is carried free from the vibrations of the rear wheel, the resilient members allowing of a long resilient movement in distinction to the short vibrations allowed by the customary single stiif sprin utilized in forks of this character.

Having described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A spring fork for a wheel, comprising a base member, a resilient member allixed at its upper end to said base member and movably connected at its'lower end to said base member, the lower end of said resilient member being further connected to the wheel axle at its lowerpoint of comiection tosaid base lower end of said base members and also connected to the wheelaxleat its point of attachment to said base member at the lower end, said spring member com osed of a pair of inter-sli 'ng parts, and resilient means to oppose the movements of said partsin both directions.

4. A spring fork for a wheel, comprising a rigid base member, a spring member secured to the upper end of said base member and also movably secured thereto at the lower end, a nd also connected to the wheel axle-at its point of attachment to said base member, at tb.e lower end, said spring member comprising a pair of intersliding members, resilient means tooppose the compression of said inter-sliding members, and a resilient means of lesser strength to oppose the extension of said inter-sliding members.

In witness that we claim the foregoing we have hereunto subscribed our names this 29th day of April, 1908.

- E. W. HOAG.

CHAS. R. KITTLE.

Witnesses:

EDMUND A. STRAUSE, OLLIE PALMER. 

